There is known a sample analyzer in which a sample tube supply unit transfers one of multiple sample tubes held in a rack to a sample rack set unit and sets the sample tube in the sample rack set unit, a sample in the set sample tube is aspirated, and a measurement unit measures the aspirated sample (see Japanese Patent Application Publication No. 2007-139462).
In the sample analyzer, in order for an operator to accommodate sample tubes in a rack, the operator needs to accommodate the sample tubes after waiting for an analyzer unit to complete measurement. In addition, it also takes some time to accommodate the sample tubes. For these reasons, some of facilities which have to process a large number of samples are subject to deterioration of sample processing performance of the device.